Iyo Melt Flow Index Inobata sei LDPE Powder Coatings Performance
Iyo melt flow index (MI), inozivikanwawo seye melt flow rate (MFR), chiratidzo chakakosha chekuyera kunyungudika kwemvura yepolyethylene LDPE poda coatings pasi petembiricha chaiyo uye mamiriro ekumanikidza. Kukosha kwayo kunobata zvakananga mashandiro ekugadzirisa, firimu-kuumba mhando, uye yekupedzisira yemuviri zvimiro zvejasi. Aya anotevera ndiwo maitiro chaiwo eiyo melt flow index pane zvivakwa zveLDPE poda coatings:
1. Kukanganisa paKugadzirisa Kuita
Fluidity uye Coating Kubudirira
Iyo yakakwira iyo melt flow index, zviri nani kuyerera kweLDPE poda munzvimbo yakanyungudutswa.
- Yakakwira MI (semuenzaniso, > 20g/10min): Hupfu hwakanyungudutswa huri nyore kuparadzira, hwakakodzera ma substrates ane maumbirwo akaomarara, makomba akadzika, kana maburi akatsetseka (semapombi uye zvikamu zvine chimiro chakakosha). Inogona kukurumidza kuzadza mapundu uye kuderedza coating leakage points.
- Yakaderera MI (semuenzaniso, <5g/10min): Iyo yakanyunguduka ine yakakwira viscosity uye isina kuyerera mvura. Panguva yekuputira, kupisa kwakanyanya kana kudzvinyirira kunodiwa; kana zvisina kudaro, matambudziko akadai sekupfeka zvisina kuenzana uye mabubbles anowanzo kuitika. Iyo inonyanya kukodzera kune ndege dzakareruka kana dzakakora coating zvinodiwa (sepamusoro pemahwendefa).
Kurapa Kumhanya uye Kubudirira Kwekugadzira
LDPE ine yakakwira MI inotonhorera uye inorapa nekukurumidza mushure mekunyunguduka, izvo zvinogona kupfupisa nguva yekurapa pamutsetse wekugadzira uye kuwedzera iyotput per unit nguva; yakaderera MI inokonzeresa kupeta kuputika nekuda kwekusaenzana shrinkage panguva yekutonhora nekuda kwepamusoro viscosity, nekudaro zvinoda nguva yakareba yekurapa.
2. Kukanganisa paKupfeka Kuonekwa
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Kufuratira uye Kupenya: Iyo yakanyunguduka ine yakakwira MI ine yakanaka fluidity. Mushure mekuputira, inogona kuyerera uye yakaenzana yakasikwa, ichigadzira yakatsetseka uye yakakwirira-gloss coating, uye kuderedza kuremara kwakadai seorenji peel uye pinholes; iyo yakanyunguduka ine yakaderera MI yakaoma kuyerera uye nhanho, uye iyo yekuputira pamusoro inowanzo kuve yakaoma nekuderera kupenya, uye kunyange sagging (panguva yakamira pamusoro pekuisa) inogona kuitika.
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Ukobvu Uniformity: Yakakwirira MI inokodzera machira akaonda (semuenzaniso, 10-50μm), uye ukobvu hweyunifomu hunogona kuwanikwa nekudzora nguva yekunyunguduka; yakaderera MI inonyanya kukodzera machira akakora (semuenzaniso, 50-200μm), asi huwandu hwekupfeka hunoda kunyatsodzorwa, zvikasadaro kuunganidzwa kwenzvimbo kana ukobvu husina kuenzana kunowanzoitika nekuda kwekushata kwemvura.
3. Kubata pane Physical Properties yeCoatings
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Adhesion: LDPE coatings nepakati MI (eg, 5-20g / 10min) ane nani adhesion: iyo yakanyunguduka haigoni kungopinda mukati madiki pores pane substrate pamusoro kuumba mechanical bonding, asiwo haizokonzeri kupindira kwakanyanya uye kurasikirwa nekuda kwekunyanya kusimba kwemvura (yakakwirira MI) kana kusabatana kwakashata nekuda kwekusakwana kweMI mvura.
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Kuomarara uye Kupfeka Kupokana: Iyo LDPE yekupfekedza ine yakaderera MI ine yakaomesesa mamorekuru cheni entanglement, uye iyo yekupfekedza ine yakanyanya kuomarara uye zvirinani kupfeka kuramba mushure mekutonhora, iyo inokodzera mamiriro ane yakakwirira zvinodiwa pamichina zvinhu (senge pasi uye maturusi epamusoro); iyo yekupfekedza ine yakakwira MI ine yakasununguka mamorekuru kurongeka, yakaderera kuomarara, uye iri nyore kukwenya, asi ine zvirinani kuchinjika.
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Flexibility uye Impact Resistance: Iyo LDPE yekupfekedza ine yakakwira MI ine zvirinani kuchinjika uye inokwanisa kumira kudiki deformation ye substrate (sekukotama uye vibration) pasina kutsemuka, iyo inokodzera nyore deformable substrates senge mapurasitiki nesimbi mashizha; iyo yekupfekedza ine yakaderera MI haina kuchinjika uye inongoita brittle kutyoka kana yakanganiswa, asi ine yakakwira zvishoma kusimba simba.
PECOAT® gadzira iyo melt flow index (MI) zvinoenderana nechigadzirwa chinofanira kuputirwa.
4.Summary
Iyo melt flow index ndiyo yakakosha parameter yeLDPE poda coatings. Pakusarudza, zvinodikanwa kunyatsoenderana maererano kugadzirisa tekinoroji (senge nzira yekubikira, mamiriro ekurapa), substrate chimiro, ukobvu hwekuputira, uye kuita zvinodiwa:
- Kune maumbirwo akaomarara, machira akatetepa, uye akakwira gloss zvinodiwa → yakakwira MI (semuenzaniso, 20-100g/10min);
- Pamachira akakora, kuoma kwepamusoro, uye kupfeka zvinodiwa zvekuramba → yakaderera MI (semuenzaniso, 0.5-5g/10min);
- Nekunamatira kwakadzikama uye kwepasirese mamiriro → yepakati MI (semuenzaniso, 5-20g/10min).
